Electrical heating unit



F. KUHN AND .I. A. HAND.

ELECTRLGAL HEATING UNIT.

APPLICA'I'iON FILED JAN-25. I917.

1,320,155. Patented Oct. 28,1919.

attomoqs UNITED STATES PATENT ()FFICE.

FRANK KUHN AND JAY A. HAND, 0F DETROIT, MICHIGAN ,ASSIGNORS TO AMERICAN ELECTRICAL HEATER COMPANY, OF DETROIT, MICHIGAN, A CORPORATION OF MICHIGAN.

ELECTRICAL HEATING UNIT.

Specification of Letters Patent.

Patented Oct. 28, 1919.

Application filed January 25,1917. Serial No. 144,368.

To all whom it mag concern Be it known that we, FRANK KUHN and JAY A. HAND, both citizens of the United States of America, residing at Detroit, in the county of Wayne and State of Michigan, have invented certain new and useful Improvements in Electrical Heating Units, of which the following is a specification, "reference being had therein to the accompanying drawings. v

The invention relates to electrical heating units of the exposed resistor type, and has particular reference to the means employed for supporting, insulating and guarding the resistor and its terminal connections as hereinafter set forth.

In the drawings:

Figure 1 is a perspective view of a unit specifically designed for use in a toaster;

Fig. 2 is an enlarged cross-section, showing one of the insulator supports for the resistor in side elevation;

Fig. 3 is a cross-section on line a7w Fig. 2;

Fig. 4c is a cross-section showing the terminal connection.

In the construction shown in Fig. 1, A is a, frame formed from a sheet-metal plate having its ed es returnbent atB to form marginal rein orcements. The plate is also cut away to form a series of bars C, which are twisted to extend in a transverse plane,

preferably at right angles to the plane of the blank. Each of the bars C is pressed to form on one side thereof a series of embossed portions D with recesses E upon the opposite side, and with apertures F centrally of and concentric with said bosses and recesses. G are insulator disks located in the recesses E and provided with apertures of smaller diameter than the apertures F. H are corresponding insulator disks placed on the opposite or embossed side of the bar, and I are hollow rivets or bushings passing through the apertures'in the insulator disks and securing the same to the bars. By reason of the fact that the disks G are held from displacement by the recesses in which they are located, the hollow rivets 0r bushings I are held centrally of the apertures F so as to be out of metallic contact with the bars C. This will thoroughly insulate the bushings and will permit of threading a naked resistor J therethrough and extending the same back and forth across the frame. Preferably the resistor J is in the form of a coil and is looped back and forth between pairs of bars C C and C C the terminal ends being attached to terminal contact pins K. These pins are secured to and insulated from the frame A by a similar'construction to that used for insulating the resistor, comprising an embossed portion L with an insulator M in the recess and an insulator N on the opposite side thereof. Connector bars P extend upward from the contact pins and are secured to the ends of the resistor.

What we claim as our invention is:

1. In an electrical heater, a sheet-metal grid, having the bars thereof integral and twisted to extend in a plane transverse to that of the blank, said bars being apertured, insulated bushings in said apertures, and a coiled resistor extending through said bushings and supported thereby.

2. In an electrical heater, a resistor sup port, comprising a grid having bars thereof twisted into planes transverse to that of the blank, said bars being apertured, the mar- .gin of said grid being reinforced and one side having an extension forming a terminal support, insulated bushings in the apertures in said bars, 'a resistor threaded through said bushings, terminals mounted on the extension of the grid and insulated therefrom, and connectors between said terminals and the ends of the resistor.

3. In an electrical heater, a resistor support, comprising a sheet-metal plate fash ioned to form a series of integral twisted cross-bars each extending in a plane transverse to the plane o'f the sheet, and integral connecting end pieces for said crossbars.

In testimony whereof we affix our signatures in presence of two witnesses.

FRANK KUHN. JAY A. HAND.

Witnesses:

HARRY W. LUYCKX, ARCHIE OAKES. 

